<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../static/js/vue.js"></script>
</head>
<style>
    .list-item {
        display: inline-block;
        margin-right: 10px;
    }

    .list-enter-active, .list-leave-active {
        transition: all 1s;
    }

    /* .list-leave-active for below version 2.1.8 */
    .list-enter, .list-leave-to {
        opacity: 0;
        transform: translateY(30px);
    }
</style>
<body>
<h2>示例：列表过渡</h2>
<div>
    同时渲染整个列表，使用 transition-group 组件。
</div>
<h2>列表的进入/离开过渡</h2>
<div id="list-demo" class="demo">
    <button v-on:click="add">Add</button>
    <button v-on:click="remove">Remove</button>
    <transition-group name="list" tag="p">
    <span v-for="item in items" v-bind:key="item" class="list-item">
      {{ item }}
    </span>
    </transition-group>
</div>

<script>
    new Vue({
        el: '#list-demo',
        data: {
            items: [1, 2, 3, 4, 5, 6, 7, 8, 9],
            nextNum: 10
        },
        methods: {
            randomIndex: function () {
                return Math.floor(Math.random() * this.items.length)
            },
            add: function () {
                this.items.splice(this.randomIndex(), 0, this.nextNum++)
            },
            remove: function () {
                this.items.splice(this.randomIndex(), 1)
            },
        }
    })

</script>
</body>
</html>
